Hey! I'm also doing this! I'll be doing both exams this year as well.
My main concerns are- not many people do it so the grade boundaries will be high.
I'm worried about learning every single little detail. I am so bad at remembering things and It kind of annoys me how philosophy is meant to be about thinking but the majority of the exams are about memorising what people have said and regurgitating it in the exam. There are the essays, but even then you have to remember who said what etc etc.
I think Ive left revision too late as well. for philosophy I started about a week ago. Ack.